Insecticidal compositions



e PU D a a m" tii-Rfi i that tilt a; FIP8501 xa ziaeei qu i; WM\ 3 fig iaswww z L v Ma 7 l 9 a p Z2.@ M) Patented Dec. 27, 19601,4,5,8-endo-exo-dimethanonaphthalene. Isodrin is the name of a productconsisting essentially of the stereoiso- 2,966,440 mer of aldrin havingthe endo,endo configuration. Di-

INSECTICIDAL COMPOSITIONS Philip Gerolt, Herne Bay, England, assignor toShell Oil Company, a corporation of Delaware This invention relates toinsecticidal compositions for use on sorptive surfaces and morespecifically to halo eldrin is the name of a product consistingessentially of the 6,7-epoxy derivative of aldrin, and endrin is thename of a product consisting essentially of the endo,endo isomer ofdieldrin. These insecticides have been found to rapidly lose theirinsecticidal potency when applied to sorptive surfaces.

It has now been discovered that the deactivation of residues ofhalogenated polycylic insecticides such as dieldrin, endrin, isodrin,and aldrin, when applied to the surfaces of materials with sorptiveproperties can be substantially inh'b'ted i f the insecticidal substancein th form of a idsolution} The attraction for the 'molecules ofihsTac'itiEidtil'Wiibstance exerted by the solid genated polycyclicinsecticides such as aldrin, dieldrin, I

isodrin and endrin which manifest extended, residrrai toxicity whenadmixed vv itrhgesinsj In the past insectic1 a mixtures have beensprayed or otherwise deposited on surfaces possessing sorptiveproperties. It has been found however, that these mixtures soon losetheir insecticidal potency. This is particularly true when theinsecticide is deposited on plant foliage, paper, soil, mud, bricks,concrete and plaster, This deactivation of insecticidal compositions isparticularly acute in hot, dry, tropical and sub-tropical areas where,for example, the interior mud walls of native houses are treated withresidual insecticidal sprays in a campaign to eliminate disease-carryinginsects. In spite of intensive research on this problem in the past, asatisfactory insecticidal composition showing extended residualinsecticidal activity when applied to sorptive surfaces has not beenfound.

It is, consequently, the principal object of the present invention toprovide insecticidal compositions which will manifest extended residualactivity when placed on sorptive surfaces.

Another object of the present invention is to provide insecticidalcompositions which manifest extended residual activity but may be easilyand economically formulated.

Yet another object of the present invention is to provide a method oferadicating insects comprising the step of exposing the insects tosorptive surfaces impregnated with these insecticidal compositions.

Other objects, features and advantages of the present invention will beapparent from the following description read in conjunction with theappended claims.

It has been established that the deactivation of insecti- 5 the interiorof the treated surface where its contact insecticidal action can nolonger be exercised. The residues of both volatile and non-volatileinsecticides lose their activity in this way. The cause of thismigration is not yet known, but appears to be connected with some powerof the sorptive material to attract the molecules of the insecticidalsubstance. This diminution of insecticidal potency by migration is notto be confused with diminu tion due to evaporation of inserticides ofrelatively high vapor pressure. The difference between these twophenomena will be immediately obvious to those well versed in the art.

Of recent years, halogenated polycydlic insecticides such as aldrin,isodrin, dieldrin and endrin have been increasingly used as the activeingredient in insecticidal sprays. Aldrin is the name of a productconsisting essentially of1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8ahexahydrosolvent is greater thanthat exerted by the sorptive material. The insecticidal substance isconsequently held on the surface of the treated material, where itcontinues to exert its residual toxicity rather than being lost in theinterior of the material.

This discovery is of the greatest importance when considered withreference to the campaign to eliminate malaria carrying mosquitos intropical areas. This campaign aims at breaking the chain of malariatransmission by spraying dwelling houses in malarial zones withinsecticide. In order to break this chain of transmission, however, theactive insecticidal agent must remain active for an extended period oftime. Though the halogenated polycyclic insecticides such as dieldrinevidence residual toxicity, under ordinary circumstances they have beenfound inadequate when applied alone to the walls of mud huts in thesetropical areas. The discovery that the solid solutions of the presentinvention maintain residual insecticidal toxicity for very extendedperiods of time, even when applied to highly sorptive mud surfacesconyet highly efiicient manner.

invention are resins, both naturally occurring and synthetic. Among thenaturally occurring resins theiinvention includes but is not restrictedto colophonyfi wood resins obtained by solvent extraction of the treestumps and branches, copal, dammar, shellac and kauri. Solid solutionsof synthetic resins are broadly encompassed by the present invention.Illustrative of synthetic resins are the coumarone resins such ascoumarone indene; resins from acetylene such as monovinylacetylene anddivinylacetylene; petroleum resins such as those sold under the nameCaterex; polystyrene and related resins; phenolic resins such as thephenol-aldehydes; alkyd and modified alkyd resins; polyvinyl esters,alcohols and acetals; the epoxy resins; and polyisocyanate resins. Solidchlorinated polyphenyls such as the Aroclors have been found veryacceptable in solid solutions of the present invention.

Intimate contact between insecticidal substance and resin may generallybe effected by grinding the two components together or by grinding themseparately and then mixing the powders together. The contact between theinsecticidal substance and the resin is considerably improved, however,if a solution of the two components in an organic solvent is evaporatedto dryness. The solid residue thus obtained may then be powdered.

Outstanding improvement in residual toxicity is obtained when a solidsolution of insecticide and resin is made by bringing the two componentsinto intimate consequently fills an urgent need in an altogether uniquetact in a homogeneous molten mixture. This may be accomplished by mixingthe solid components and heating and stirring the mixture until ahomogeneous liquid is obtained. Alternatively, one of the components maybe melted and the other solid component then added, with stirring andheating if necessary, until a homogeneous melt is obtained. The twocomponents may also be separately melted and the liquids then mixed. Thesolid solvent used in this fusion process should have a softening pointin the range of 50 to 250 C. The essence of this fusion is the intimatemixture of the components while in a homogeneous state.

The homogeneous molten mixtures thus obtained may then be allowed tocool en masse and the solidified melt converted into particulate form byone of the numerous well known means such as crushing in a hammer millor in an air jet mill. Any difficulty in grinding due to slighttackiness of the solidified melt may be mitigated either by adding aninert particulate filler of the type used in com pounding agriculturaldusts to the molten mixture before it is allowed to cool or by addingsuch a filler to the solidified melt during grinding. The molten mixtureof insecticidal substance and amorphous solid may also be sprayed oratomized into an inert gaseous medium such as air, or into a liquid withwhich it is immiscible, such as water, or onto a solid carrier,preferably in powder form. The ratio of insecticide to resin may varygreatly without departing from the scope of the invention. Thus a rangeof insecticide to resin of from 1:10 to :1 is within the scope of thisinvention. A range of insecticide to resin of from 1:2 to 2:1 ispreferred, however.

The solid solutions of insecticide and resin thus formed are vastlysuperior to the compositions made by grinding or by evaporation from anorganic solvent and constitute the preferred compositions of thisinvention. The present invention encompasses both saturated, supersaturated and unsaturated mutual solid solutions.

The particulate solid mixture of insecticidal substance and solidsolvent may be utilized as a dust, preferably after dilution with aninert powder filler of the type generally employed in the manufacture ofdusts for the agricultural and horticultural industries. Attaclay or ahighly absorbent carrier such as Hi-Sil 233, a synthetic precipitatedhydrated silicon dioxide may be employed. The invention is not limitedto these specific diluents however. Thus among the many diluents andcarriers which may be successfully employed for the purposes of thepresent invention are the diatomites such as diatomaceous earth, calciumlimes, calcites, dolomites, gypsum, mica, talc, pyrophylites, members ofthe montmorillonoid group such as bentonite, kaolinites, andattapulgites as well as other naturally occurring and synthetic diluentsand carriers.

Preferably the particulate solid mixture is formulated as a wettablepowder by incorporating a minor proportion of a surface active agent,for example the sodium salts of secondary alkyl sulfuric acid estersavailable under the registered trademark Teepol, a non-ionic emulsifiersuch as the alkyl aryl polyether alcohol sold as Triton X-100(registered trademark) or a deflocculating agent, i.e. a substancehaving definite deflocculating or dispersing properties as distinct fromwetting properties, although wetting properties may also be present to aminor degree. Suitable deflocculating agents are, for example, certaincommercially available products such as Pinex sulfite lye, Goulac,Leukanol, Intraphore and Tamol. Goulac is a lignin pitch, Leukanol is acondensed sulfonic acid dispersing agent, and T'amol is a sodium salt ofcondensed aryl sulfonic acid. If necessary, both a surface active agentand a deflocculating agent may be incorporated. Inert powder fillers andwater conditioning agents such as sodium polyphosphates may also beincorporated. The solid solvent used in the above wettable powderformulations should, of course, be substantially insoluble in water.

The compositions of the invention may also contain substances such asurea and hexamethylene tetramine which stabilize the insecticidalcomponent against decomposition when in contact with materials of anacidic nature. Other biologically active substances, such as otherinsecticidal compounds and acaricidal and bactericidal compounds mayalso be incorporated if desired.

The following examples illustrate the compositions of the invention andthe improvement in residual toxicity obtained when these compositionsare applied to panels made of laterite mud.

EXAMPLE I Dieldrin was melted with equal weights of coumarone resin,Aroclor 5460, chlorinated polyphenyl compound, colophony, and sulfur,respectively, to form homogeneous solutions. The solid products obtainedon cooling were mixed with 5 percent by weight of Teepol and ground toparticles of sizes from 10 to 50 microns. The resulting powders weresuspended in water and sprayed on dry panels of laterite mud,approximately one half inch thick, at the rate of 25 milligrams ofdieldrin per square foot. The panels were stored under dry conditions atabout 30 C. and the toxicity of the spray residues tested at intervalsbyallowing house flies (M usca domestica) to be in contact with them for30 seconds and then determining the percentage knockdown at hourlyintervals and the mortality of the flies 24 hours after contact with thespray residue. Comparative tests were carried out with a commercialdieldrin 50% wettable powder diluted with water and applied at the samerate to similar laterite mud panels. Similar tests were carried out witha commercial aldrin wettable powder for comparison and an aqueoussuspension of a solidified molten mixture of aldrin and an equal weightof coumarone resin, applied at the rate of 25 milligrams of aldrin persquare foot.

The results of these tests are summarized in Table I.

Table I [Percentage knockdown and 24-hour mortality of M urea domeslz'caafter 30 seconds exposure to dieldrin residues (25 nag/sq. it. on mudpanels)] N umber of Hours After Exposure Formulation Age of Residuedieldrin (50% wettable powder).

dieldrin 1 leoumarone resin (50:50).

dieldrin/chlorinated polyphenyl (Aroclor 5460) (50:50).

dieldrin/colophony tutti-.111:

dieldrin/sulfur aldrin (50% wettable powder).

H u- Ooooomuncoumh-Qoqo 1 month.

See footnotes at end of table.

5. Table l-Continued [Percentage knockdown and 24-hour mortality ofMusca domestica after 30 selcgiiids exposure to dieldrin residues (25mgJsq. ft. on mud pane s sults obtained with a commercial 50% dieldrinwettable powder are included for comparison. The results of the testsemploying dieldrin resin compositions are summarized in Table III.

Table III Number of Hours After Exposure Formulation Age of [Percentageknockdown and 24hour mortality of llfusca domastica after Residue 30Seconds exposure to residues of different dieldrin coumarone resin 1% 23 4 5 6 24 combinations (25 mg. dieldrin/sq. it.) on mud panels] 5335? 8g g l) t l 1- 10 Formulation Age of Res NumberofHours after Exposurealdrin oumaron e i iijli 3 3 g 8 ii 8 [due 1% 2 a 4 i 5 6 24 1month.-.-0 0 o 0 0 0 2s Mortality in the controls was 3% or less. dieldrin (50%wettag 3 3 n "'6 "'6' Residues tested for the second time. ble powder).0 O 0 0 0 (1 5 Dieldrin dosage 12.5 milligrams per square foot. 0 0 0 00 0 0 It is readily apparent that the deposits from the comin m r n 3 8"59 "66' igg mercially available dieldrin and aldrin wettable powders gg 2 lg 8 are rapidly deactivated. The compositions of the ,in- 0 0 0 010 27 87 vention, however, retain their activity for considerablydieldrin/coumarone g g g lgg longer periods. Thus, compositionscontaining dieldrin re in i md o ,0 0 0 6 so 94 as the toxicant arestill producing 100% mortality of the (5WD)- 8 g g 18g flies within 24hours after exposure to a spray residue 0 e as 100 which was 10 weeksold. Aldrin alone causes only 8% dieldrin/coumarone g g g; g; tgg tggmortality after 3 days while the solidified molten mixture 25inmate/(16mm)- lmonth 5 1s 76 95 100 100 of aldrin and coumarone resincauses 65% mortality 3 0 8 67 72 87 100 days after spraying, 61%mortality 2 weeks after spraying and 28% mortality one month afterspraying. Simi- Mortality in the contmls was 2% less' lar tests withisodrin and endrin also evidenced the su- It be Seen that although qresults perior residual toxicity of these resin compositions to 30 minedIn each Case, t Pr d ct Obtamed by melting the the insecticide when usedalone tvlvo components together was superior to the other formu ations.EXAMPLE H EXAMPLE 1v Dieldrin, aldrin, isodrin and endrin were eachmelted A 2:1 dieldrimcoumamne Sample was prepared as m ,vanous propomonswlth colfmamne resm and the follows: 4 g. of 2:1 dieldrin-coumaroneindene mixture solid products obtamed on cooling w lormulated as wasmelted in an oil bath, mixed well and cooled quickly wettable powdersand tested as described m Example I. with Dry The solid was then groundin a mortal- The results of the Showmg the l l and with Dry Ice and thewetting suspending agents, Duponol marone resin composition aresummarized in Table II. ME Dry and Marasperse DuponoyME Dry is a TableII fatty alcohol sulfate, Marasperse N is a salt of lignin [Percentageknockdown and 24-hour mortality of Musca dome-trim after ulfomc All ofthe l i material was Suspended 30 seconds exposure to residues ofdieldrin/coumarone resin (25 mg. I I 00 Of Water COIltalIllHg 0.25% Marsperse N- dieldrln/ ht mud paws] The composition evidenced excellentresidual toxicity ac- Number Hours after Exposure tivity when applied tomud panels. Formulation Ageiglflgtes- EXAMPLE V 1% 2 3 4 5 6 24 A 2:1dieldrin-coumarone sample was prepared as follows: 4 g. of 2:1dieldrin-coumarone indene mixture dieldrin/coumarone g 3 8 was melted inan oil bath, mixed well and cooled gradresin 90:10. lmomh" 0 11 44 76 8589 m ually by allowing to stand at room temperature afterdieldrin/coumarone g g gg g; 3 igg the addition of suspending agents.All of the ground res1n70:30. 'i: O 11 40 69 82 93 100 material wassuspended in 200 m1. of water containing dieldrin/coumarone Egg- 8 g g gg igg 0.25% Marasperse N. The composition evidenced eximonth'l'.-. o 221 52 65 71 100 cellent residual activity when applied to mud panels.

There was no mortality in the controls. 55 EXAMPLE VI It can be seenthat although the formulations con- Various formulations were madeemploying y taining a high dieldrin to resin ratio initially cause aWeight dieldrin, 25% y Weight resin, y Weight higher mortality thanthose in which the dieldrin to M r p CB, 10% y Weight Duponol ME y andresin ratio is low, after 24 hours 100% mortality is ob- 60 18% yWfiight Attaclay (Containing 5% l All mi d i ll cases, formulations wereprepared from a 2:1 dieldrin-resin EXAMPLE III melt which wasquick-cooled, cut back with surfactants Wettable powders each containing50 percent by weight anddAttaclay f and i f Tests were of dieldrin,aldrin, isodrin or endrin were prepared (a) con.ucted.on Ormu atlonscontammg each of the folby mixing the powdered insecticide and powderedlowing resms' coumarone resin, (b) by dissolving the insecticide andcoumarone resin in acetone, evaporating the solvent and Name and SuppherType Q OE grinding the cooled mixture, (0) by grinding a solidifiedmolten mixture of the insecticide and coumarone resin. Ester G N1200,Reieho1d Pure'gum resin ester 65-72 To the resultmg Pmducts 5PerFem by weght of P ngii iie i fo. 1116, Reichold Modified phenolresins 132-154 was added. Aqueous suspensions of these formulationsChem. Co. a \I C d in were then sprayed on mud panels at a dosage of 25b f m maronem mews 108417 milligrams of dieldrin per square foot and theresidual g oxidizing 35 toxicity determined at intervals after spraying.The reog al hi in jjjjjjj 1204726 Name and Supplier Type 811211201 BatuBold Scraped Gum Dado 168-180 mar, Scheel Go. Red Yacca Gum, Scheel Codo 110-128 Pentalyn N, Hercules Powder Pentaerythritol ester of 110-119Co. rosin-low acid number. Peltalyn K, Hercules Powder Pentaerythritolester of 189-197 0. rosin. Vinsol Ester Gum, Hercules Glycerol ester ofvinsol 140-155 Powder Co. Peitalyn A, Hercules Powder Pentaerythritolester of 109-116 0. rosin. 8L Ester Gum, Hercules Pow- Glycerol ester ofpale wood 89-96 der C0. rosin. Synthe Copal Ester Gum,

Reiehold Chem. Co. Levisol 33, Hercules Powder Malteic alkyd modifiedrosin 115-165 0. es er. Cellolyn 102, Hercules Powder Modifiedpentaerythritol 132-140 Co. ester of rosin. Poly-Pale Ester 10, HerculesGlycerol ester of polymer- 109-110 Powder Co. ized rosin. Piccolyte-125, Penna. Inc. Hydrocarbon terpene resin 125 Chem. Corp. PiecolasticD-150, Penna. Inc. Polymer of styrene 145 Chem. Corp. Piceopale' 100,Penna. Inc. Polymerized unsaturates 97-103 Chem. Corp. derived from deepcracking of petrole m. Nebony 80, Neville Co Hydrocarbon dark colored98-106 thermoplastic resin. Nevidene (R-G), Neville Co."Coumarone-indene 126 Neville Resin (R-16A), do 65-85 Neville C0.Paradene No. 1, Neville Co .-do 65-85 Paradene No. 2, Neville Codo86-100 Nuba N o. 2, Neville Co Dark thermoplastic resinous 86-105 pitces. Argclor 5460, Monsanto Chem. Chlorinated terphenyl 0. Flash CrackedAsphalt, Shell Petroleum resin 89 Development Go.

D do 173 Kerr Mac Resins, Kerr-Me- -.do 155 Gee Oil Co. Lube CrudeAsphalt, Shell do Development Co. Neville Chlorinated Resin,Chlorinatedhydrocarbon Neville Co. Chlorowax 705, Diamond Al-Chlorinated paratlins 100 kali Corp. Alkydol 105, Alkydol Labora-Polymerized rosin ester 100-105 tories Inc.

These compositions evidenced excellent residual activity when applied tomud panels.

It will be understood that although the examples show specificquantities and types of insecticidal compounds and resins, the inventionis not to be construed as limited except by the hereto appended claims.

Having thus described this invention in full what is desired to beprotected by United States Letters Patent is: 1. An insecticidalcomposition comprising a solid solution of an insecticide and a solidresin, the weight ratio of said insecticide to said resin lying withinthe range of from about 9:1 to about 3 :7, the insecticide beingselected from the group consisting of 1,2,3,4,l0,lO-hexachloro-1,4,4a,5,8,8a-hexahydro-1,4,5,8 endo exo dimethanonaphthalene,1,2,3,4,l0,10-hexachloro-l,4,4a,5,8,8a-hexehydro- 1,4,5,8-endo endodimethanonaphthalene, 1,2,3,4,l0,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a octahydro-1,4,5,8-endo-exo-dimethanonaphthalene and1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a octahydro 1,4,5,8-endo-endo-dimethanonaphthalene, and the resin being sclccted from thegroup consisting of colophony, copal, wood resins, dammar resin,shellac, kauri resin, coumarone resins, monoand poly-vinylacetyleneresins, petroleum resins, styrene resins, phenol-aldehyde resins, alkydresins, polyvinyl ester resins, polyvinyl alcohol resins, polyvinylacetal resins, epoxy resins, polyisocyanate resins, chlorinatedpolyphenyl resins, sulfur, gum resin esters, rosin ester resins,hydrocarbon tcrpene resins, and chlorinated parafiin resins.

2. An insecticidal composition comprising a solid solution of aninsecticide and a coumarone-indene resin, the weight ratio of saidinsecticide to said resin lying within the range of from 9:1 to 3:7, theinsecticide being selected from the group consisting of1,2,3,4,10,10-hexachloro-1, 4,4a,5,8,8a-hexahydro-1,4,5,8-endo-exodimethanonaphthalene, 1,2,3,4,10,IO-hcxachloro-l,4,4a,5,8,8a-hexahydro-1,4,5,8-endo-endo dimcthanonaphthalene, l,2,3,4, 10,10-hexachloro-6,7-epoxy-l,4,4a,5,6,7,8,8a-octahydro 1,4,5,8-endo-exo-dimethanonaphthalene and 1,2,3,4,lO,10-hexachloro-6,7 epoxy1,4,4a,5,6,7,8,8a octahydro 1,4,5,8- endo-endo-dimethanonaphthalene.

References Cited in the file of this patent OTHER REFERENCES Mfg.Chemist, May 1956, pp. I and 191.

Handbook of Aldrin, Dieldrin and Endrin," Shell Chem. Corp., December1954.

1. AN INSECTICIDAL COMPOSITION COMPRISING A SOLID SOLUTION OF ANINSECTICIDE AND A SOLID RESIN, THE WEIGHT RATIO OF SAID INSECTICIDE TOSAID RESIN LYING WITHIN THE RANGE OF FROM ABOUT 9:1 TO ABOUT 3:7, THEINSECTICIDE BEING SELECTED FROM THE GROUP CONSISTING OF1,2,3,4,10,10-HEXACHLORO-1,4, 4A,5,8,8A-HEXAHYDRO-1,4,5,8 - ENDO - EXO -DIMETHANONAPHTHALENE,1,2,3,4,10,10-HEXACHLORO-1,4,4A,5,8,8A-HEXEHYDRO1,4,5,8-ENDO - ENDO -DIMETHANONAPHTHALENE,1,2,3,4,10,10HEXACHLORO-6,7-EPOXY-1,4,4A,5,6,7,8,8A -OCTAHYDRO-1,4,5,8ENDO-EXO-DIMETHANONAPHTHALENE AND1,2,3,4,10,10-HEXACHLORO-6,7-EPOXY-1,4,4A,5,6,7,8,8A - OCTAHYDRO -1,4,5,8ENDO-ENDO-DIMETHANONAPHTHALENE, AND THE RESIN BEING SELECTED FROMTHE GROUP CONSISTING OF COLOPHONY, COPAL, WOOD RESINS, DAMMAR RESIN,SHELLAC, KAURI RESIN, COUMARONE RESINS, MONO- AND POLY-VINYLACETYLENERESINS, PETROLEUM RESINS, STYRENE RESINS, PHENOL-ALDEHYDE RESINS ALKYDRESINS, POLYVINYL ESTER RESINS, POLYVINYL ALCOHOL RESINS, POLYVINYLACETAL RESINS, EPOXY RESINS, POLYISOCYANATE RESINS, CHLORINATEDPOLYPHENYL RESINS, SULFUR, GUM RESIN ESTERS, ROSIN ESTER RESINS,HYDROCARBON TERPENE RESINS, AND CHLORINATED PARAFFIN RESINS.